1. Field of the Invention
The present invention relates in general to data networks and more particularly, to a method and apparatus for implementing a data frame processing model.
2. Background of the Invention
Fibre Channel is a computer communications protocol designed to provide for higher performance information transfers: Fibre Channel allows various existing networking protocols to run over the same physical interface and media. In general, Fibre Channel attempts to combine the benefits of both channel and network technologies.
A channel is a closed, direct, structured, and predictable mechanism for transmitting data between relatively few entities. Channels are commonly used to connect peripheral devices such as a disk drive, printer, tape drive, etc. to a workstation. Common channel protocols are Small Computer System Interface (SCSI) and High Performance Parallel Interface (HIPPI).
Networks, however, are unstructured and unpredictable. Networks are able to automatically adjust to changing environments and can support a larger number of connected nodes. These factors require that much more decision making take place in order to successfully route data from one point to another. Much of this decision making is done in software, making networks inherently slower than channels.
Fibre Channel has made a dramatic impact in the storage arena by using SCSI as an upper layer protocol. Compared with traditional SCSI, the benefits of mapping the SCSI command set onto Fibre Channel include faster speed, connection of more devices together and larger distance allowed between devices. In addition to using SCSI, several companies are selling Fibre Channel devices that run Internet Protocol (IP).
With increasing use of Fibre Channel, there is an increased need for efficient transfer of data between Fibre Channel devices and non-Fibre Channel devices. This data transfer requires that the originating protocol be translated to the protocol of the destination network/channel. Traditional protocol bridges process data frames in an inefficient manner which introduces a latency in the frame-based data flow. As such, there is a need for an improved system for bridging network protocols.